Bridge costruction.



H. P. BURDEN. BRIDGE CONSTRUCTION.

APPLICATION FILED MAR. 15, 1912. 1,096,348. Patented May 12, 1914. Fig-1"fig; 3 3 "1* c V .m m f g g i; m A

mmmulllllllumml l Fig.4 {m lk w in": M; h P ffll P J wimsss 5 0 0 -2 ki' UNITED STATES PATENT OFFICE.

HENRY PERCY BURDEN, OF MONTREAL, QUEBEC, CANADA.

BRIDGE CONSTRUCTION.

1 '0 all whom it may concern:

Be it known that I, HENRY PERCY Bonner, a subject of the King of GreatBritain, a resident of the city of Montreal, Province of Quebec,Dominion of Canada, have invented certain new and useful Improvements inBridge Construction; and I do hereby declare that the following is afull, clear, and exact description thereof.

My invention relates particularly to the bridge floor and is equallyapplicable to the floors of new and old bridges.

It has for its object to provide a floor structure, the members of whichwill maintain proper relative positions under strains heretofore thecause of disorganization, and,

at the same time, prevent accidents by the spreading of the rails.

Further objects of the invention are to increase the life of the bridgefloors, simplify the construction thereof, facilitate repairs, andreduce the labor necessary to effective maintenance.

The invention consists, broadly speaking, of a bridge structure havingtransverse permanent members, permanent longitudinal members, a seriesof ties supported on the longitudinal members, the end ties of suchseries lying in tight contact with and braced against the transversemembers, and a series of alined metallic devices lying upon the surfaceof and engaging and preventing lateral and longitudinal displacement ofthe said ties and maintaining the proper gage of the rails, the latterbeing particularly important in preventing the accidents and loss oflife due to the spreading of the rails, the width of the portions of thedevice resting upon the ties being less than one-half the width of suchties.

The invention also consists of the construction, specific combination,and particular arrangement of parts hereinafter dc scribed and pointedout in the claims. For full comprehension, however, of my invention,reference must be had to the accompanying drawings forming a part ofthis specification in which similar reference characters indicate thesame parts, and wherein Figure 1 is a plan view of a portion of arailway-bridge embodying my invention; Fig. 2 is a longitudinal verticalsectional view thereof; Fig. 3 is a transverse vertical sectional View;Fig. 4 is a detail perspective view of one of the members of the alinedSpecification of Letters Patent.

Application filed March 15, 1912.

Patented May 12, 1914.

Serial No. 683,975.

series for preventing displacement of the ties in both lateral andlongitudinal directions relatively to the bridge, and also the spreadingof the rails; Fig. 5 is an enlarged detail sectional view illustratingthe manner in which the members illustrated in Fig. t prevent bunchingand separation of the ties; and Fig. 6 is a detail perspective viewillustrating the feature disclosed in Fig. 5 independent of the rails.

in the present embodiment of the invention the permanent transverse andlongitudinal bridge members consist of floor beams b ant a respectively,the top flanges of the floor beams rising a short distance above the topflanges of the stringers. Upon these stringers and between the beamflanges are supported a series of ties (Z (Z held in place by hook-boltse piercing some of the ties, engaging the outer edges of the flangedheads of the stringers c, and tightened in place by nuts f. These tiesare spaced and retained against rela. tive displacement by a series ofplates of special construction and particular a1 'angement and coactingwith the permanent trans verse members. These plates indicated at g arepreferably rolled and of slightly oblong form in plan view with fourspikeholes 70 near the corners and a longitudinal surface rib m in linewith two of the spike-holes and presenting with the plate at its sidetoward the middle of the plate a true right angle n.

The under side of the plate has a pair of transverse ribs 0 equallyspaced from its transverse center line and with their opposite sidespresenting with the under surface of the plate true right angles. Theseribs are so spaced, relatively, that their opposite sides will beseparated by a distance equaling the predetermined standard spacing ofthe tics; and they are augmented in their function by a pair ofknife-edge transverse ribs p rolled upon the underside of the plate atthe ends thereof and serving the additional purpose of means preventingdisplacement of the plates longitudinally relatively to the ties, theportions of the plates resting upon the ties being less than onehalf thewidth of the ties.

The ribs 0 are of sulliciently greater depth than the ribs to act asabntmcnts against which the ties will come into contact when shifted toproper position for spacing purposes.

In assembling a bridge floor containingmy invention, the top flanges ofthefloorbeams being, as before mentioned, above the level of the topflanges of the stringers, the required number of ties are thrown looselyupon the stringers between the beams, and starting at one end the firsttie is shifted into tight contact with the beamfa pair of the plates arethen placed in proper position, the second tie shifted to positiongripping the flanges 0 betweenit and the first tie, the depth of theseflanges 0 permitting of this, and the flanges p are driven into theties. In this manner the complete floor is rapidly assembled with theend ties in tight bearing relation with the beams, and all the tiesequally spaced in accordance with standard requirements and both tiesand plates held against displacement in either longitudinal ortransverse directions relatively to the bridge. After the floor has beenthus assembled the rails r are placed in position, the gage beingestablished in the usual way and the spikes are driven, the onlyadjustment not automatically provided by the above combination being theplacing of the plate in proper position relatively to the center-line ofthe floor.

The height shown of the top flanges of the floor beams relatively to theties is preferred for stability of the latter, and filler blocks 5present an even continuity of the rail support. The plates are also usedindependently of the rails and located at the side edges of the floor,in which case they are reduced slightly in size, and the surface ribs mare dispensed with. This arrangement gives a pleasing finish to thefloor and has all the advantages as regards maintenance referred toabove. These improved plates serve the purpose of tie spacers and theusual tie plates for distributing the pressure of the rails over greaterarea of the ties thereby increasing the life of the tie.

If desired the invention can be applied to the ties forming the floor ofa bridge, such plate having transverse tie spacing flanges upon itsunderside and the portions of such plate outside of the flanges andadapted to rest upon the ties being less than one half the width of thesaid tie; and flanges of less depth than and parallel to the transverseflanges for engaging the ties.

3. In bridge construction, an alined series of plates adapted to lieupon the t1es form; ing the bridge floor each plate having a pair I oftransverse middle flanges upon the underside thereof constructed andarranged to project between the ties and act as abut ments for thelatter when shifted beneath the plates, the portions of such platesoutside of the flanges being less than one-half the width of the tiesspaced thereby for the purpose of permitting the plates of the alinedseries to have one end rest upon the same tie as the contiguous end ofthe adjoining plate. y

In testimony whereof I have signed my name to this specification in thepresence of two witnesses at Montreal, March 7th, 1912.

HENRY PERCY BORDEN.

l'Vitnesses GonDoN G. Coonn, E. R. PITTS.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. C. i

